Pediatric palliative care (PPC), focused on the care of children with serious illnesses and their families, has developed dramatically over the past decade. Despite these developments, the field struggles with an underdeveloped capacity to gather and analyze a sufficient amount of high-quality data to guide PPC treatment and decision-making for individual patients, and cost data to inform PPC policy at the population level. Accordingly, the Pediatric Palliative Care Research Network (PPCRN) proposes to create a prospective cohort of 800 PPC patients initiating or continuing care with well-established hospital-based PPC teams at 4 large children's hospitals across the United States, focusing on 3 related tasks. First, we will create a shared prospectively collected clinical database. We will convene a PPCRN SHAred Data and REsearch (SHARE) Committee, which will oversee the specification of data to be collected, the process of data collection and entry into a research-standard database, and management and use of the resulting data source. SHARE data will include patient demographic and diagnostic information; patient (or parent, if patient cannot answer) reported symptoms; goals of care and changes of goals over time (regoaling); and other data elements agreed upon by the PPCRN SHARE Committee. Second, we will integrate the prospective clinical data with hospital administrative data (including hospital costs as well a many other detailed aspects of daily hospital care) from a consortium of children's hospitals in the United States. The composite SHARE database will provide a wealth of information regarding hospital-based care for this cohort of patients. Third, we will use SHARE data to study PPC patterns of All Children Costs, Outcomes, Hospital- based Utilization and Non-utilization Trajectories (PPC-ACCOUNT), addressing 3 hypotheses: H1: Distinct patterns of change over time exist for patient symptoms, parent distress, and goals of care. H2: These trajectories are related to each other and to hospital cost trajectories. H3: Early receipt of PPC ameliorates patient symptoms and parent distress, and lowers hospital costs. This innovative multicenter study of PPC will 1) provide a rigorous, comprehensive description of the most prevalent and distressing symptoms among both children and their parents receiving PPC services, 2) significantly advance understanding of the relationships between children's symptoms, parental symptoms and stress, and hospital-based health care utilization, and 3) create a prospective multicenter data source and research infrastructure resources for future PPC investigators.